Before smartphone computational photography came along -- in the conventional camera era -- it used to be a given that the eye was better than the sensor, or film.
Please, don't confuse your misconception of what dragging the shutter speed would do in your day to day usage vs what professions do with long exposure.
Sure, adding motion blur is an effect one can achieve with long exposure. You need some extra things like ND filters to avoid over exposing, but that a technique someone is specifically looking to achieve. It's not a mistake from something my mom would do.
We've been using long exposure for things like light painting well before Apple/Google. We've been using long exposure for astrophotography for a long time as well. I still feel utter respect for Hubble et al night after night manually guiding the scope to keep the image in frame. In fact, the same frame of film would be exposed for multiple hours each night for multiple nights before finally being developed.
What you've associated things with in your mind does not mean the rest of the world only associates the same things in the same way.
Light painting is not about compensating for low light. On the contrary, it typically involves reducing the ambient light in order to manually "paint" with a light bulb for artistic effect.
Which part of the above are you debating?
I like your "reducing the ambient" to really let me know you have no clue what I'm referring to, but that's okay. this whole thread is just wasted energy
Blurring is frequently the goal. Blurring waterfalls is a popular technique. As is blurring the ocean. Or streaking of light from cars. Searching for "long exposure" shows these techniques.
They use tripods to keep some things static. Smartphones can make those photos just as well as cameras with the computational photography turned off. The limitation is using neutral density filter to make exposure work.
um, ackshully, lots of computational editing is being done now. The image of Sag A* was heavily computed. They are now having to use computed images to remove all of the made on earth objects in the sky from Starlink to planes. There's a lot of stuff done to astroimages now and computational editing is making its way there.